Icker



UNITED STATES PATENT OEEICE.

JOHN DANIEL BOEDIOKER, OF NEIV YORK, N. Y.

PIANO-FORTE ACTION.

Specication forming part of Letters Patent No. 33,633, dated November 5, 1861.

b all whom t may concern:

Be it known that I, JOHN DANIEL Bonn- ICKER, of New York, in the county and State of New York, have invented a new and Improved Piano-Forte Action; and I do hereby declare that the following is a full and exact description of the same, reference being had to the accompanying drawing, and to the letters of reference marked thereon.

The nature ot myinvention consists in the employment of a combination of levers applied to and connected with the hammershank and arranged in such a manner as to act, together with the jack, upon the hammer' so as to move and arrest the same within a short distance from thel string to allow the jack to operate the same, so as to produce a repetition of blows by a very slight rise of the end of the key.

In the accompanying drawing, A represents the key, to which the jack B and back-check C are attached in the usual manner. D is the rest, E the flange to which the hammerbutt G of the hammer H is pivoted, and I is the hammer-shank. To this hammer-shank I two levers `n and m are hinged. The after end of the lever m extends close to the hammer-butt G. The lever n is arranged so that its after end acts against the under side of the forward end of the lever m, and is provided at its forward end with a small spiral spring s, acting against the hammer-shank I, close to the hammer H. The forward end of the lever m is acted upon by a regulatingscrew t, passing through the hammer-shank I, so as to regulate the motion of said levers. Instead of this screw fr, a wedge or its equivalent may be applied for the purpose of regulatin g the motion of said levers.

The operation is as follows: By the motion of the key A the jack B acts upon the buttend G of the hammer II in the usual manner, so as to cause the hammer H to strike the string X, after which and while the key A is still compressed the hammer will be caught by the back-check O in its fall in the usual manner. The jack B escapes during this operation from the notchin the hammer-butt G and passes under the after end of the lever m, acting upon the same, in

combination with the momentum of the fall of the hammer, so that the forward end of said lever m operates the lever n, so as to compress thereby the small spiral spring s between the end of said lever ln, and the hammer-shank I. As soon as the playing end of the key A is permitted to risein thc slightest perceptible degree, or only just sufficient to liberate the hammer from the back-check O, the spring S will expand again, causingthereby the lever n to act upon the lever my, so as to force the after end of said lever m down ward; but, as before mentioned, the jack B stands below this after end of said lever m. The hammer II will thereby, through the'action of said spring S, be lifted upward, so as to come within a short dista-nce of the string X, and will be supported in this position by the combined action of the levers 'It and m, spring S, and jack B. By this upward motion of the hammer the jack B will receive a slight motion, so as to bear partly upon the end of the lever m and partly upon the hammer-butt G, in which position a very slight motion of the key A will cause the jack B t0 act upon the hammer and permit thereby a quick repetition of the blows. rIhe distance the hammer will be supported away from the string X depends upon the amount of motion given to the levers n and m, which may be regulated by means of the screw c passing through the ham mer-shank I and acting upon said levers, as before mentioned.

YVhat I claim as my invention, and desire to secure by Letters Patent, is-

l. The arrangement of the levers n and m, in combination with the hammer-shank I and acted upon by the jack B, in the manner and for the purpose substantially as described. Q. The use of the spring S between the end of the lever In and the hammer-shank I, opelating' the levers n and m, and, in combination with the jack B, the hammer H, in the manner and for the purpose substantially as set forth. 3. The screw c orits equivalent acting upon the levers m and n, substantially as specified.

JOHN DANIEL BOEDICKER. Vitnesses:

HENRY E. RoEDEE, JOHN THOMAS DavrDsoN. 

